package com.rd.student.jiaji.class3.wangyanbo.day0731;

import java.util.ArrayList;
import java.util.Collections;

public class Test1 {
    public static void main(String[] args) {
        ArrayList a=new ArrayList();
        for (int i=0;i<50;i++){
            a.add(i);
        }
        Collections.shuffle(a);
        for (int i=0;i<20;i++) {
            System.out.println(a.get(i));
        }
    }

}

